Humidity and temperature control



Feb. 13, i934. G H, H HE 1,946,903

7 HUMIDITY AND TEMPERATURE CONTROL Filed Oct. 23, 1950 INVENTOR.

E Georgefifibhez; BY

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A TTORNEYJ Patented Feb. 13, 1934 PATENT oFFicE HUMIDITY AND TEMPERATURE CONTROL George H. Fisher, Wabash, Ind., assignor to Minneapolis-Honeywell Regulator Company, Wabash, Ind., a corporation of Delaware Application October 23, 1930. Serial No. 490,580

1 Claim.

The present application relates to humidity and temperature control, and more particularly to control of the humidity and temperature in apartment and oflice buildings, though the invention may be applied to the control of temperature and humidity conditions in any other unit comprising a plurality of chambers. The primary object of the invention is to provide a method of and apparatus for controlling the humidity and temperaiure conditions of a plurality of chambers in accordance with the average temperature and humidity conditions existing in such chambers. Further objects of the invention will appear as the description proceeds.

In the accompanying drawing:

Fig. 1 is a broken section through a building comprising a plurality of chambers;

Fig. 2 is a side elevation, par.ly in section, of a unit of the control mechanism on an enlarged scale; and

Fig. 3 is a fragmental view of a modification.

Referring more particularly to the drawing, it will be seen that I have illustrated a heating plant 10 having a draft door 11 adapted to be operated by a connection 12, and having a check draft (not shown) adapted to be operated by connection 13. The connections 12 and 13 are operable by suitable known mechanism indicated generally at 14, said mechanism being under the control of a temperaiure responsive unit indicated generally at 15. A main 16 is adapted to conduct heated fluid from the heating plant 10 to a stack or header 17 to which are connected a plurality of supply pipes 18'having their radiator or heat dispensing means situated in the various chambers 19, 20, 21, 22, 23 and 24.

As shown, the header 17 is mounted in a suitable shaft which may be an elevator shaft or a shaft constructed specifically for the purpose, and in said shaft there is also positioned a stack 25 to which are connected intake units 26, one for each of the chambers, by means of conduits 27. The intake members 26 are preferably provided with thermostatically operated shutter elements, so constructed and arranged as to provide full opening only during periods when the chambers in which they are mounted are at optimum temperatures; and to reduce the opening at times when the temperature drops below or rises above the predetermined optimum value. Since shutters of this type are known, no further description thereof in the present specification is deemed to be necessary.

At its lower end the stack 25 communicates with the intake port or a suitable air pump or fan indicated at 28, the movable element of said pump or fan being driven through a belt 29 or otherconnection from a motor 30 or other power means. The outlet conduit 31 of said pump 28 has mounted therein the temperature responsive unit 15. v

In the embodiment illustrated in Fig. 1, said conduit 31 leads into the lower portion of a shower cabinet 32 or other humidifying device, said cabinet 32 being provided with a water supply conduit 33, flow through which is controlled by a valve 34 operable by a handle or arm 35. A conduit 36 leads from said shower cabinet 32 and connects to a header 37 disposed in the above mentioned shaft and communicating with a plurality of pipes 37', one for each of said chambers 19, 20, 21, 22, 23 and 24.

A unit indicated generally at 38 and of such character as to respond to humidity conditions is provided with a dry bulb 39 disposed in the conduit 31 and containing temperature responsive fluid, such as sulphur dioxide. The bulb 39 is not completely filled with liquid sulphur dioxide, and consequently it has an evaporating and a condensing surface, so that any change in temperature affecting the bulb will produce an immediate corresponding change in the vapor pressure in the bulb. A flexible diaphragm 40 closes the open upper end of the bulb 39, thus separating the same from a tube 41 which communicates with a motor 42 of the diaphragm type. Preferably the tube 41 is filled with oil or other similar liquid, so that the motor will not be afiected by ambient temperature, but will be responsive solely to variations of temperature in the conduit 31.

The unit 38 comprises also a second bulb 43 similar to the bulb 39, similarly partially filled with volatile liquid such as sulphur dioxide, and surrounded by a wick 44 dipping into a waterfilled pan 45 suspended in the conduit 31 upon a bracket 46. A filler tube 47 is provided for maintaining water in the pan 45. A flexible diaphragm 48 separates the chamber formed by the tube 43 from an oil filled pipe 49 communieating with a diaphragm motor 50.

The unit 38 also comprises a stationarily mounted slide 51 upon which is adjustably supported a fulcrum block 52. Upon the fulcrum block 52 is mounted an arm 53, a weighted arm 54 being fulcrumed at 55 and connected to said arm 53 by a link 56 to counter-balance the weight of the arm 53. The motor 42 is positioned and constructed to bear downwardly upon the arm 53, while the motor 50 is positioned and constructed to bear upwardly thereon.

A link 57 connects the arm 53 to one arm 58 of a bell crank lever 59, and the other arm 60 of said lever is connected by a link 61 with the arm 35 of the valve 34.

The operation of the apparatus should be apparent. It being presumed that the motor 30 is operated to drive the fan 28, it will be apparent that air is drawn from each of the chambers 19 and 24 through the header 25, the amount of air drawn from any one chamber being dependent upon the temperature of that chamber, since temperatures above or below normal tend to close the intake units 26. The air so drawn from the chambers is mixed in the header 25 and is blown by the fan 28 through the conduit 31. The temperature of the current of air flowing through the conduit 31 will obviously be a function of the temperatures of the atmosphere in the various chambers. The temperature of this mixture, being impressed upon the temperature responsive element 15, will operate to control the setting of the draft doors of the heating plant 10. The temperature responsive mechanisms 1415 may take any well known form, it being understood that the thermostatic element 15 controls the mechanism 14 to open the draft door 11 when the temperature of the air impressed upon the element 15 is below an optimum value; and to close said door when such temperature is above said optimum value.

The temperature of the mixture being impressed upon the bulbs 39 and 43 will also affect the unit 38. Obviously there will be a differential in the pressures generated in the tubes 39 and 43 because of the cooling efiect of the' evaporation from the wick 44. Thus the pressure in the tube 39 will always be higher than the pressure in the tube 43. It will be obvious that the elements of the unit 38 may be ad- Justed to bring about a given position of the arm 53 in response to a given differential between the pressures generated in the tubes 39 and 43. It will also be obvious that variations in the humidity of the current of air passing through the conduit 31 will effect variations in the differential between these pressures, increases in humidity decreasing the differential, and decreases in the humidity increasing the differential. Thus, a drop in the humidity of this stream of air below the normal for which the unit is set will effect a counter-clockwise movement of the lever 59, resulting in an opening movement of the valve 34 to increase the flow of water to the shower cabinet 32, thusraising the humidity of the air passing through the conduit 36 and header 37 to the chambers. Correspondingly, a rise in the humidity of the air stream passing through the conduit 31 will effect a closing movement of the valve 34.

In the embodiment illustrated in Fig. 1, the conduit 31 discharges into the cabinet 32, so that the organization effects merelya closed circulation of air through'the building. In Fig. 3, I have shown a modification in which the conduit 31' discharges to the atmosphere and a conduit 62 connected to a separate fan (not shown) leads fresh air to the shower cabinet 32' and so through the conduit 36 to the chambers.

I do not claim novelty specifically in the unit 38 which is merely an adaptation of the humidity responsive unit disclosed in the patent to Carrier No. 1,554,784, issued September 22, 1925.

I claim as my invention:

The method of controlling the humidity of the atmosphere of a plurality of chambers which consists in passing a flow of air through humidifying apparatus to all of said chambers,

preparing a mixture of quantities of air from said chambers by drawing greater quantities from chambers of optimum temperature than from warmer or cooler chambers, and controlling the flow of water to said humidifying apparatus in accordance with the humidity of such mixture.

GEORGE H. FISHER. 

